The present invention is directed to creating high gloss, light fast toner images. Specifically such images are created by applying a mixture containing a clear, abrasion resistant toner resin and a light fast material to the toner image.
In the practice of conventional xerography, it is the general procedure to form electrostatic latent images on a xerographic surface by first uniformly charging a charge retentive surface such as a photoreceptor. The charged area is selectively dissipated in accordance with a pattern of activating radiation corresponding to original images. The selective dissipation of the charge leaves a latent charge pattern on the imaging surface corresponding to the areas not exposed by radiation.
This charge pattern is made visible by developing it with toner by passing the photoreceptor past one or more developer housings. In monochromatic imaging, the toner generally comprises black thermoplastic powder particles which adhere to the charge pattern by electrostatic attraction. The developed image is then fixed to the imaging surface or is transferred to a receiving substrate such as plain paper to which it is fixed by suitable fusing techniques.
Recently, there has been a great deal of effort directed to the development of color copiers/printers which utilize the xerographic and/or ink jet imaging process. Such efforts have resulted in the recent introduction of the Xerox.TM. 5775.TM. copier/printer, the Xerox 4900.TM. and the Fuji Xerox A-Color 635.TM. machine.
Notwithstanding all the recent development in the area of color printers and copiers there is room for improvement in the quality of color images on paper and synthetic substrates such as Mylar.TM. and Teslin.TM..
Following is a discussion of additional prior art, incorporated herein by reference, which may bear on the patentability of the present invention. In addition to possibly having some relevance to the question of patentability, these references, together with the detailed description to follow, should provide a better understanding and appreciation of the present invention.
U.S. Pat. No. 5,337,132 granted to Abraham Cherian on Aug. 9, 1994 discloses the creation of simulated photographic prints using xerography. This patent utilizes a print creation apparatus comprising a pair of platens, one of which is heated for adhering an imaged transparency to a backing sheet. The imaged transparency and the backing sheet are supported on a hard surface such as tempered glass during the adhering procedure. A predetermined pressure is applied by the platens simultaneously with the application of heat. U.S. patent applications Ser. Nos. 08/095,639, 08/095,622, 08/095,016, 08/095,136 and 08/095,639 cited in the '132 patent are also incorporated herein by reference.
U.S. Pat. No. 5,413,840 (Mizuno) discloses a decorative laminated sheet having a sense of being coated and having improved surface hardness, which is produced by laminating a polyester film excellent in transparency on the surface of a semi-rigid thermoplastic resin film supplied with a colored layer or a pattern-printed layer, and then coating a hard coat layer comprising a UV-curable coating on the surface of the polyester film of the resulting laminated film, and a process for producing the same. The invention of the '132 patent can provide a sheet not only excellent in scratch resistance, specular reflectivity and sharpness of the surface, but having a sense of being deeply coated as well.
U.S. patent Ser. No. (Attorney's Docket No. D/95463) discloses a method of creating simulated photographic-quality prints using non-photographic imaging such as xerography. As disclosed therein, a reverse reading image is formed on a transparent substrate which is adhered to a backing sheet containing a right reading image corresponding to the reverse or wrong reading image. The method provides a simulated print which exhibits enhanced optical density compared to prints where only a reverse reading image is used.
U.S. Pat. No. 4,997,697 (Malhotra) discloses a transparent substrate material for receiving or containing an image which comprises a supporting substrate base, an antistatic polymer layer coated on one or both sides of the substrate and comprising hydrophilic cellulosic components, and a toner receiving polymer layer contained on one or both sides of the antistatic layer, which polymer comprises hydrophobic cellulose ethers, hydrophobic cellulose esters, or mixtures thereof, and wherein the toner receiving layer contains adhesive components.
U.S. patent application Ser. No. 07/828,821 filed on Sep. 31, 1992 discloses a method and apparatus for enhancing color fidelity in a printing process employing an intermediate member wherein a developing unit deposits a colorless and transparent material directly onto an intermediate member before transfer of any color toner images thereto. Alternatively, a developing unit first deposits the colorless and transparent material on a latent image member. The colorless and transparent material is then transferred to the intermediate member before transfer of any color toner images thereto.
Various approaches have been devised to enhance the appearance of a color copy. The following disclosures may be relevant to various aspects of the present invention:
Pond, Xerox Disclosure Journal, Vol. 2, No. 5, p. 17 (September/October 1977), describes depositing a layer of fine colorless toner particles on the electrostatic image of a photoconductor, followed by depositing a second layer of larger color toner particles.
Drappel et al., European Pat. Application. 0424093 (published Apr. 24, 1991; corresponds to U.S. Pat. No. 5,176,974 assigned to Xerox Corporation), describes forming a "peel layer" on an imaging device. Latent images are formed and developed on the "peel layer," and the "peel layer" is subsequently simultaneously removed from the imaging member and transferred and affixed to a substrate. The use of a transparent waxy toner is disclosed.
Sako et al., J02201453 (English language abstract; published Aug. 9, 1990), describes developing the electrostatic latent image formed on an image carrier with chromatic toners, then developing the entire surface of an image forming region with colorless, transparent toner.
Sako et al., J02201452 (English language abstract; published Aug. 9, 1990), describes mixing a color toner for making an electrostatic latent image visible with a colorless, transparent toner.
Tagawa et al., J02140757 (English language abstract; published May 30, 1990), describes developing what seems to be color toner images over the entire surface of a transfer member by using a colorless toner containing wax of a low melting point as a release agent.
Hirano et al., J63080269 (English language abstract; published Apr. 11, 1988), describes a developer composed of a color toner and a colorless, transparent toner.
Kawabata, J63058374 (English language abstract; published Mar. 14, 1988), describes an image forming method which develops the surface of the photosensitive body with a colorless, transparent toner.
Bares, Xerox Disclosure Journal, Vol. 16, No.1, p. 69 (January/February 1991), describes applying a transparent (unpigmented) toner as a final finishing step.
Fukushima et al., U.S. Pat. No. 3,901,698 (issued Aug. 26, 1975), describes a method of reversal development using two developers wherein the first developer consists of colorless or white, positively charged, toner particles.
Mammino, U.S. Pat. No. 4,064,285 (issued Dec. 20,1977), describes a method of decalcomania wherein the polymeric "subbing" layer is colorless.
Clemens, U.S. Pat. No. 4,066,802 (issued Jan. 3, 1978), describes a method of decalcomania wherein the interposed polymeric sheet is colorless.